In agriculturally advanced countries such as the United States of America, in the last century cotton harvesting has evolved from a largely manual task, to a completely automated task, wherein self-propelled machines are used to pick cotton at rates of up to several thousand pounds per hour from many rows of plants simultaneously. Reference in this regard Watkins U.S. Pat. No. 1,763,607 issued Jun. 10, 1930; Fachini et al. U.S. Pat. No. 4,341,423 issued Jul. 27, 1982 to International Harvester Co.; and Covington et al. U.S. Pat. No. 4,993,216 issued Feb. 19, 1991 to J.I. Case Co.
While technological innovation and advancement have led to the use of technologically advanced, large capacity cotton harvesting machines in advanced nations, in poorer, less developed nations, cotton is still largely harvested by hand. Even old, relatively simple cotton harvesters such as disclosed in Watkins U.S. Pat. No. 1,763,607 are not now known to be used in developing countries for harvesting cotton.
One anticipated shortcoming of using a harvester such as shown in Watkins, is the possible abrupt stoppage and jamming of the harvesting mechanism, for instance, due to abrupt stoppage of the wheels, such as if one or both of the wheels become lodged in a ditch or the like, or in the event the harvesting mechanism becomes entangled with thick cotton foliage, weeds, vines or the like. This possibility would appear to be increased if the harvester is only manually powered.
One reason that this is a problem is an apparent lack of ability to disengage the picking apparatus from the drive wheels. The Watkins harvester also has a relatively blunt forward end, such that it would appear that large or wide cotton plants may be difficult to guide and receive into the relatively narrow front opening of the harvester. Also, using more modern harvesting mechanisms including picker rotors including columns of picker spindles and drives for rotating them, doffer columns, and the like, in a harvester such as disclosed in Watkins, would likely make the harvester too heavy to be moved under human power.
Further, it is desirable that spindles or other picking elements of the harvesting apparatus be moving in timed relation to the ground speed of the harvester, so as to enter a cotton plant to remove the cotton therefrom at a speed closely corresponding to the speed of the harvester over the ground. It has been found that if the harvesting mechanism is operating too fast relative to the speed of movement of the plant through the harvester, a result like a threshing effect may occur which can result in the plants being damaged and debarked. In contrast, when the harvesting mechanism operates too slowly relative to ground speed, it has been observed that the plant can be undesirably pulled by the spindles or other harvesting elements, even to such an extent as to partially or completely uproot the plant.
Thus, what is sought is a walk-behind type cotton harvester that overcomes many of the shortcomings and limitations set forth above.